热托6911拖拉机工作3000小时后,不少车的变速箱响声大,快慢杆掉档。拆检后发现,都是因为花键轴前端支承的两个R28×33×13滚针轴承滚针损坏所致(见图)。滚针2损坏后,花键轴3前支点失去约束,变成悬臂轴,工作时摇摆厉害,使二轴前端的两个K40×45×17滚针早期磨损,并使二轴及轴套在二轴上的快慢档滑动齿轮摆动,从而造成快慢杆掉档。滚针损坏的原因有以下五点:1 润滑油不足或脏污;2.机车长期固定作业,润滑油激溅不利;3.冷季 Thermo 6911 tractor 3000 hours after the work, many cars gearbox loud, fast rod off the file. Disassembled found that both because of spline shaft front bearing two R28 × 33 × 13 needle roller needle damage caused (see Figure). After the needle 2 is damaged, the front fulcrum of the spline shaft 3 loses its restraint and becomes a cantilever shaft, which oscillates vigorously during work so that two K40 × 45 × 17 needle rollers at the front end of the two shafts are worn early, Two-axis speed gear sliding gear swing, resulting in slow rod off the file. Rolling needle damage for the following five points: 1 lack of oil or dirty; 2 locomotive long-term fixed operation, oil splash adverse; 3 cold season